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Updated: Jun 23, 2026

Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
Gigahertz Cutoff Frequencies and High Gain in Graphene-Based Hot-Electron Transistor Enabled by Material Engineering
Carsten Strobel1, André Heinzig1, Andre Hiess1
1Institute of Semiconductors and Microsystems, Chair of Nanoelectronics, Technische Universität Dresden, Nöthnitzer Straße 64, 01187 Dresden, Germany.
Abstract:
Graphene (Gr)-based hot-electron transistors (GHETs) offer high potential for high-frequency applications due to the extremely thin nature of graphene as a base material. For the first time we present GHETs with excellent DC device characteristics and gigahertz operation achieved by an optimization of the emitter-base (E/B) composition. The optimized E/B composition enables more efficient injection of hot electrons into the base, thereby improving charge transport and reducing scattering losses. As a result, a record-high measured common-emitter current gain beta of 42 was achieved using a SiO2/Gr E/B structure. Moreover, when using a MoS2/Gr E/B junction the maximum output current is increased to record values of approximately 2000 A/cm2, representing a significant improvement in performance over previous devices. Furthermore, cutoff frequencies of close to 1 GHz are determined for nonoptimized SiO2/Gr-based devices. The experimentally observed device characteristics are very promising for future high-speed nanoelectronics.
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